74. THE "SOLDIER EMPERORS," 180-284 A.D. THE LATER EMPIRE, 180-395 A.D. The period called the Later Empire covers the two hundred and fifteen years from the accession of Commodus to the final division of the Roman world at the death of Theodosius. It formed, in general, a period of decline. The very existence of the empire was threatened, both from within and from without. The armies on the frontiers often set up their favorite leaders as contestants for the throne, thus provoking civil war. Ambitious governors of distant provinces sometimes revolted against a weak or unpopular emperor and tried to establish independent states. The Germans took advantage of the unsettled condition of affairs to make constant inroads. About the middle of the third century it became necessary to surrender to them the great province of Dacia, which Trajan had won. [1] A serious danger also appeared in the distant East. Here the Persians, having overcome the Parthians, [2] endeavored to recover from Roman hands the Asiatic provinces which had once belonged to the old Persian realm. Though the Persians failed to make any permanent conquest of Roman territory, their constant attacks weakened the empire at the very time when the northern barbarians had again become a menace. "IMPERIAL PHANTOMS" The rulers who occupied the throne during the first half of this troubled period are commonly known as the "Soldier Emperors," because so many of them owed their position to the swords of the legionaries. Emperor after emperor followed in quick succession, to enjoy a brief reign and then to perish in some sudden insurrection. Within a single year (237-238 A.D.) six rulers were chosen, worshiped, and then murdered by their troops "You little know," said one of these imperial phantoms, "what a poor thing it is to be an emperor." [3] POLITICAL SITUATION IN 284 A.D. The close of the third century thus found the empire engaged in a struggle for existence. No part of the Roman world had escaped the ravages of war. The fortification of the capital city by the emperor Aurelian was itself a testimony to the altered condition of affairs. The situation was desperate, yet not hopeless. Under an able ruler, such as Aurelian, Rome proved to be still strong enough to repel her foes. It was the work of the even more capable Diocletian to establish the empire on so solid a foundation that it endured with almost undiminished strength for another hundred years. [Illustration: THE WALL OF ROME Constructed by Aurelian and rebuilt by Honorius. The material is concrete faced with brick, thickness 13 feet, greatest height 58 feet. This is still the wall of the modern city, although at present no effort is made to keep it in repair.] 75. THE "ABSOLUTE EMPERORS," 284-395 A.D. REIGN OF DIOCLETIAN, 284-305 A.D.